Category: Space Flight

Cape Canaveral’s Titan launch pad gantry was demolished on Sunday. The tower was built in the 1990’s to support the US Air Force Titan 4 rocket program. The site has been used for NASA missions as well, including the launch of the Cassini-Huygens Saturn mission in 1997. Launch Complex 40 is being demolished and then refurbished to make way for the new SpaceX Falcon rocket launch facility. Now the gantry is rubble, the clean up operation can begin…

At 9am on Sunday, April 27th, 200 pounds of high explosives brought the Complex 40 mobile service tower crashing down. The tower was responsible for housing and preparing the highly successful Titan rockets for launch. Mainly used for military payloads, the Titan 4 series also sent the NASA Cassini probe on its way to Saturn on October 15th, 1997. A Titan 4 rocket was also used to send the ill-fated Mars Observer mission to the Red Planet on September 25th, 1992. Mission controllers lost contact with Observer when it was three days away from orbital insertion.

The gantry weighed nearly 6500 tonnes and was installed with an advanced satellite processing clean room. The tower supported a total of 17 launches, deploying sophisticated surveillance and communication satellites for the US government. Two of these launches were devoted to the NASA interplanetary missions. The last Titan 4 was launched three years ago, handing heavy launch duties over to the modern Atlas 5 and Delta 4 rocket systems. In its glory days Titan 4 was the largest rocket available carrying the heaviest payloads into space.

View the complete series of images taken of the demolition of the Complex 40 tower »

Now that the tower has been removed, Space Exploration Technologies (SpaceX) can begin to set up the commercial launch site as the East Coast base of operations for its Falcon 9 rocket system which is currently under development. But why can’t the tower be renovated for SpaceX launches? The Falcon 9 rocket system will be assembled horizontally and rolled to the launch pad shortly before launch; the gantry is therefore superfluous to the company’s needs at Complex 40.

However, not all the infrastructure of the site will be removed. The launch pad’s concrete deck and flame duct, water deluge system, electrical systems, lightning towers and instrumentation in the bay under the pad will be reused. The existing office space will also be renovated for SpaceX use. Since last October, SpaceX employees have been working at the site, removing any equipment not compatible with the Falcon system. The site will be up and running in time to begin supplying the International Space Station when NASA’s Space Shuttle fleet is retired in 2010. Complex 40 will live on, minus gantry, for NASA contracted launches and other commercial satellite orbital insertions by SpaceX.

Sources: SpaceX, Spaceflight Now

What happens when a robotic space probe breaks down millions of miles away from the nearest spacecraft engineer? If there is a software bug, engineers can sometimes correct the problem by uploading new commands, but what if the computer hardware fails? If the hardware is controlling something critical like the thrusters or communications system, there isn’t a lot mission control can do; the mission may be lost. Sometimes failed satellites can be recovered from orbit, but as there’s no interplanetary towing service for missions to Mars. Can anything be done for damaged computer systems far from home? The answer might lie in a project called “Scalable Self-Configurable Architecture for Reusable Space Systems”. But don’t worry, machines aren’t becoming self-aware, they’re just learning how to fix themselves…

When spacecraft malfunction on the way to their destinations, often there’s not a lot mission controllers can do. Of course, if they are within our reach (i.e. satellites in Earth orbit), there’s the possibility that they can be picked up by Space Shuttle crews or fixed in orbit. In 1984 for example, two malfunctioning satellites were picked up by Discovery on the STS-51A mission (pictured above). Both communications satellites had malfunctioning motors and couldn’t maintain their orbits. In 1993 Space Shuttle Endeavour (STS-61) carried out an orbital mirror-change on the Hubble Space Telescope. (Of course, there’s always the option that top secret dead spy satellites can be shot down too.)

Although both of the retrieve/repair mission examples above most likely involved mechanical failure, the same could have been done if their onboard computer systems failed (if it was worth the cost of an expensive manned repair mission). But what if one of the robotic missions beyond Earth orbit suffered a frustrating hardware malfunction? It needn’t be a huge error either (if it happened on Earth, the problem could probably be fixed quickly), but in space with no engineer present, this small error could spell doom for the mission.

So what’s the answer? Build a computer that can fix itself. It might sound like the Terminator 2 storyline, but researchers at the University of Arizona are investigating this possibility. NASA is funding the work and the Jet Propulsion Laboratory is taking them seriously.

Ali Akoglu (assistant professor in computer engineering) and his team are developing a hybrid hardware/software system that may be used by computers to heal themselves. The researchers are using Field Programmable Gate Arrays (FPGAs) to create self-healing processes at the chip-level.

FPGAs use a combination of hardware and software. Because some hardware functions are carried out at chip-level, the software acts as FPGA “firmware”. Firmware is a common computer term where specific software commands are embedded in a hardware device. Although the microprocessor processes firmware as it would any normal piece of software, this particular command is specific to that processor. In this respect, firmware mimics hardware processes. This is where Akoglu’s research comes in.

The researchers are in the second phase of the project called Scalable Self-Configurable Architecture for Reusable Space Systems (SCARS) and have set up five wireless networked units that could easily represent five cooperating rovers on Mars. When a hardware malfunction occurs, the networked “buddies” deal with the problem on two levels. First, the troubled unit attempts to repair the glitch at node level. By reconfiguring the firmware, the unit is effectively reconfiguring the circuit, bypassing the error. If it is unsuccessful, the unit’s buddies perform a back-up operation, reprogramming themselves to carry out the broken unit operations as well as their own. Unit-level intelligence is used in the first case, but should this fail, network-level intelligence is used. All the operations are performed automatically, there is no human intervention

This is some captivating research with far-reaching benefits. If computers could heal themselves at long-distance, millions of dollars would be saved. Also, the longevity of space missions may be extended. This research would also be valuable to future manned missions. Although the majority of computer issues can be fixed by astronauts, critical systems failures will occur; using a system such as SCARS could perform life-saving back up whilst the source of the problem is being found.

Source: UA News

There is a nagging problem under the surface of the excitement surrounding the future of long-term missions into space. Human exposure to the high amounts of solar radiation and other sources of cosmic rays is likely to be the main factor that could curtail mankind’s dreams for future manned settlements on other planets. The effects of radiation exposure to astronauts is not fully understood, but could range from acute radiation sickness (perhaps after being caught in an intense solar storm during interplanetary transit) to gradual cellular damage, greatly increasing the risk of cancer in long-term missions. So what can we do about it? Mankind is highly adaptive and some countermeasures are gradually being realized. (And yes, the Russian Space Monkeys might be able to help…)

The problem comes when humans leave the protective blanket of the Earth’s magnetic field. Acting like a huge, invisible force field, the magnetosphere deflects most of the harmful high energy particles being fired from the Sun. Anything that penetrates this barrier is quickly absorbed by our thick atmosphere. Even at high altitudes, in low Earth orbit, some protection to astronauts can be provided (although the ambient radiation is far higher up there than down here). So when we talk about colonizing other planets and sending astronauts further and further into deep space, radiation exposure becomes a bigger risk.

An immediate concern is that astronauts may get caught in a solar storm, where the Sun (usually around solar maximum) ejects huge clouds of highly energetic protons. If the storm is intense enough, huge doses of radiation could be inflicted on the men and women in space. Roughly, a dose of 500 rads or more will kill a human in two to three hours, and a smaller dose could cause acute radiation sickness. Radiation sickness could be fatal in weeks should the astronaut not receive urgent medical care. How about the long-term, gradual impact of prolonged exposure to higher-than-normal doses of radiation? This is an area of space medicine that we do not completely understand as yet.

In new research by the Lombardi Comprehensive Cancer Center at Georgetown University Medical Center, the high-energy nature of radiation in space may lead to premature aging and prolonged oxidative stress in cells. This also suggests that astronauts risk a higher than normal risk of cancers, such as colon cancer, through exposure to “high linear energy transfer” (LET) radiation. LET radiation consists of the high energy protons emitted by the Sun and cause a huge amount of damage to small areas of tissue.

“Radiation exposure, either intentional or accidental, is inevitable during our lifetimes, but with plans for a mission to Mars, we need to understand more about the nature of radiation in space. There is currently no conclusive information for estimating the risk that astronauts may experience.” – Kamal Datta, M.D., assistant professor at Lombardi and lead author.

With NASA’s Project Constellation on the horizon, there has been a focus on the long-term effects of interplanetary radiation. Ultimately, this project aims to send humans to the Moon and Mars, but there are strong indicators that astronauts will face in increased cancer risk and lifespan reduction, a massive hindrance to a mission spanning several months or a thriving proto-settlement.

This is where the lab mice help us out. The amount of “free radicals” (highly reactive molecules often linked with cancer and cell aging) were measured and found that the mice developed highly oxidative (i.e. full of free radical molecules) gastrointestinal tracts when exposed to space-like high-LET radiation. The Lombardi group concluded that the mice had developed a high risk to various cancers, particularly gastrointestinal cancers. They also noticed that after exposure (even after two months), the mice prematurely aged, signifying that the effect of radiation damage can persist long after exposure to a high-LET environment.

So what can we do? There are several plans in motion to further test the effects of radiation on humans and to predict when astronauts will be at risk. This week, Russia announced (controversial) plans to send monkeys back into space, possibly as far as Mars. Once the shock of this “outdated” proposal wore off (the previous Russian space monkey program ran out of funding in the 1990’s), it became very clear as to what the Russian space agency is hoping to achieve: to have a better understanding of the long-term exposure to a high-LET environment on the human physiology. Many will argue that this practice is cruel and unnecessary, but others will say monkeys are used in experiments every day, why shouldn’t they help us in the ultra-modern world of space travel? The jury is still out on this debate, but there are many ways to investigate and counteract the radiation effect on humans.

There are also many systems in place to protect mankind from the onslaught of solar storms. Using the Solar and Heliospheric Observatory (SOHO) and other craft located between the Earth and Sun, an early warning system has been set up to provide astronauts on orbit with some time to take cover should a solar flare be launched Earth-bound. This system is fully operational and has already proven itself. Recently, I toyed with the idea of a similar Mars-based early warning system, providing future Mars colonies with about 40 minutes advanced notice of an incoming solar storm.

Shielding is another obvious protective measure. Lunar and Mars colonies are most likely going to use large amounts of regolith to block the incoming particles. Only a few meters of locally dug-up regolith will provide excellent protection. But what about the journey to Mars? How will the astronauts of projects such as Constellation be protected? Perhaps an advanced “Ion Shield” might work?

Whatever the effect of radiation on humans in space, it seems obvious that we are in the infancy of space flight and we are already addressing some of the most difficult problems. Over the next few years, much effort will be focused on the health of astronauts, hopefully finding some answers to the space radiation problem.

Original source: Georgetown University Medical Center

On Friday Russian officials unveiled a monument to Laika, the pioneering dog that led the way to manned spaceflight on November 3rd, 1957. Her little memorial is a model dog standing atop a rocket near a military research facility in Moscow. When she made the historic flight into space on board Sputnik II, very little was known about the effects of launch and zero-gravity on an animal and Laika wasn’t thought to make it. Due to her being so small and hardy, she made it into orbit, but this was a one way ticket, she had no idea there would be no coming home… be warned, this isn’t a happy tale…

The dogs chosen for the Russian space program were usually stray mongrels as it was believed they could survive and adapt in harsh conditions. Also, small dogs were chosen as they could fit into the capsule and were light for launch. Two year old Laika was apparently chosen from the animal shelter in Moscow for her good looks. After all, the first Russian into space would need to be photogenic. There was intense excitement about her selection for participation in the space race and she endeared herself to scientists and the public; she was described as “quiet and charming”.

Unfortunately Laika’s trip was far from humane. She had to wait for three days before launch locked inside the capsule whilst technical problems with the launch were fixed. Operators had to keep her warm by pumping hot air into her cockpit as the temperatures around the launch pad were freezing. Once the launch was successful, doctors were able to keep track of her heartbeat and her blood pressure. The official story was that her heartbeat was fast at the launch, but she calmed down and was able to eat a specially prepared meal in orbit.

There are mixed reports about what happened next, but the official Soviet version was that Laika was able to live in space for a week, and then she was euthanized remotely. However, after the Soviet Union collapsed, reports from mission scientists suggested that she only lived for a couple of days and was put down, or (most likely) the cabin overheated soon after orbital insertion, killing her within hours.

Interestingly, scientists did not announce that she was to die in orbit until after she was launched. Sputnik II was not equipped with a re-entry system and the craft burned up in the atmosphere after 2,570 orbits on April 14th, 1958.

It is easy for us to look back on Laika’s journey distastefully, but in the days of the Cold War, there was huge pressure on scientists to produce results in the Soviet Union and the USA. Sending dogs and other “guinea pigs” (I wonder, have any actual Guinea Pigs been sent into space?) into orbit was the most viable means to understand the effects of space travel. Regardless, she paved the way for other orbiting dogs (to be safely returned this time) and by 1961, enough data had been gathered to send the first man into space: Yuri Gagarin.

Original source: Associated Press